Antislipping attachment for



March 13, 1945.

Edward 6. Marinetti ByT-KMMM.

' .Aitor-71e Patented Mar. 13, 1945 Vuhu-.Tito

STATES PATENT oFFlcE CRUTCHES WilliamI L.` McGroryl George H. Pemberton, and? `Edward G. Marinetti, East Providence, R. I.

Application November 4, l943, Serial No. 508,986

(Cl. 13S- 53) 8 Claims.

Ourf invention relates `to improvements in` crutches and comprises an anti-slipping attachrrientadapted tobe secured to the shortened end of.' a'. crutch shankof such a length as to complete with saidl shortened crutch shank the desiredllength` of the crutch...

`Qur inventionincludesa spike whichvmay bev selectively advanced by Athe vcrutch user beyond;

the tip of the. crutch `shank if desired `in use,

grip of the crutch.

preferablyfroma point adjacentthe usual hand An object of our invention Iis to provide `an attachment of this description' in which all `operating parts are contained in the'attachment, itself below the shortened end, of the crutch,

whichI provides a construction not requiring any cutting. or any other manipulation ofthe short-- 'cned crutch end `forthe operationfof the' working parts therein. 1

A further objectofourirvention isto providev in. a device of this` description a structure which permits the ready replacement of spikes as they wear. out inusewithout taking` the attachment itselfoif the lower crutch end. v

A further' object of our invention lis to provide a. device `wherein the spike and handle may be readily TemOVed, if desired, for use inthe summer time.

For this purpose., wefprovide a hollow tubular member having. anl upper end` adapted tobe detachably secured. to the-lower end of the shank and means operable. from without said tubular member, including a portion projecting inwardly through a `bayonet joint slot in the tubular mem-l ber to thejupper end ofthe spike. lDifficulty has been experienced indevices of this description in having, snow, fidirt, or other objects either .bej coming encrusted on or movingin through` the slotte. affect the-operation thereof.. `A further object-ot our. invention. thereforeis [to provide anv 'axially and circumferentially Ymovable guide adapted'at all times to cover the bayonet joint slot and also movable in use .to` breakup anyaccumulationjof snow, j ice, ,mud` etc., thereon.

These. and suchother objects of ourinvention asmay hereinafter appear will be bestunderstood from adescription. of. theA accompanying drawing which{illustrates` an. embodiment thereof.

4"JiritlieQdrav'ving. Fig. Lisa side elevation .of a` crutchhaving our improved-attachment attached` to thelower vend of the shank thereof.

Fig. 2 is an enlarged elevational View lof4 the lower end of. said crutch. includingour attach- ,tion` Afrom the. lowerfend. thereof. l

ment withtlre spike `projecting to a-grippingfposiy Fig. 3 is an elevational viewv like Fig.`2 with the spike withdrawn from below the tip of the crutch` Fig. 4 is a disassembled perspective view of the parts of our improved attachment.

Fig. 5 is a vertical central sectional View of I the lower end of the crutch with myinventio'n` attached with the parts in the position shown in Fig. 3.

In the drawing, wherein'likecharacters of ref erence generallyindicate like parts throughout. I0 generally indicates a crutch. Our invention is particularly adapted for use with a' standard type of crutch l0 having the usual spaced side bars .l 2.

with the lower ends thereof tapering as at I4 to each other, an arm rest I6 mounted across the top of said bars and ahand grip I8 mounted llocthe desired length of tliecrutch. If desired,

projection 26 of less diameter than the crutch shank 2|] may project downwardly therefrom at the lowerend of the crutch and may, if desired, be externally threaded as at 28. Our improved attachment includes a tubular member 30 having its upper end 32" adapted tovs'urround and ,be

` secured to the lower end or'tip V`2`ll of the crutch shank or'projecton 26 when employed. The member also has a central hollow portion 3ft projecting below th'e lower end'of the crutch shank which is preferably provided with a bay` cnet joint slot36 therein. We `provide the'spike 38 with a pointed lower end' 4B' and an 'upper 4end 42 movable` withinv the'` central `hollow portion 34 of'said tubular rnember` and means such as a spring 44icor'1tain'ed` within theA said hollow portion 34- of said tubular member 30, normally urg'- ing said spike 38' withiny said tubular member. We also provide' means` for urging said spike Iaxially of said crutch shank to `gripping position comprising anoperating rod-ll'fhaving an inner endlldetachably securableto the upper end 42--of-said spike; a'locking radial= portion lill-for movement within. said bayonet joint slotteand l anloperating handle portion 52 beyond said radial portion 5ll ,in our preferredembodiment extendall tion 58 of said operating rod exterior of said tubular member 30.

In our preferred embodiment said parts are preferably constructed as follows: The upper end 32 of said tubular portion is preferably internally threaded as at -29 so that said upper end may be threaded on the threaded tip 26 of the shank 28 externally threaded as at 28 for this purpose, the bayonet joint slot 36 has the portion 35 extending vertically and axially `of said central portion 34 or of said tubular member 30 and a portion 3l extending circumferentially from the lower end of said axially extending portion 35. The lower end of said tubular member is preferably internally threaded as at,6l. The upper end 42 of the spike 38 is provided with a socket 64 internally threaded as at 66 in the tip thereof and a washer-shaped portion 68 projecting radially outwardly therefrom. Said portion 68 may be integral with the upper end of said spike or may comprise a washer secured thereto. The detachable plug 56 is preferably externally threaded as at lll and said lower end 58 of said tubular member 30 is preferably cooperating internally threaded as at 6|. of said plug 14 is also preferably provided with the diametric turning slot 'I6 for receiving the end of a screw driver for threaded securement and removal of theplug within the lower ,endv

58 of the tubular member 38. The crutch is also preferably provided with the usual resilient tip 18 having a base 88 having a central spike hole 82 therein and a circumferential side wall 84 embracing the lower end 58 of the tubular *mem-4 ber 30. The means to normally urge the spike 38 within the lower end of said tubular member 30 and the base 80 of said tip 18 preferably comprises spring means 44 interposed between said washer-shaped projection 68 and the top 85 of said plug. In the embodiment shown the means for urging said spike 38 axially of said crutch shank so that the pointed end 48 thereof may project beyond the lower end of said crutch preferably comprises the operating rod 46, which has an axially extending lower end 48 contained within the hollow central portion 34 of said tubular member 38', preferably externally threaded as at 49. which is preferably threaded within the hol-I low socket 42 at the upper endof said spike 38. provided with the gripping internal threads 66 for this purpose. The locking portion 5|) projects radially outwardly from said threaded lower end 48 through said bayonetjoint slot 36 to exterior of said tubular member'30 to form with the cir" cumferential portion-31 of said bayonet joint slot 36, a locking bayonet joint. In the preferred embodiment sb own said operatingrod also has the portion 52 projecting vertically upwardlyfrom the radial portion 50 exterior of said guard sleeve 62 and terminating in a handle 54 adjacent the crutch hand grip I8. Means such as the guide eyes 90 and 82 may be provided for loosely securing said upwardly projecting rod portion 52 to said crutch. In the embodiment shown the guard' sleeve 62 for said bayonet joint slot 36 is split as at 63 and is provided with aligned partiallycircular holes 65 therein substantially centrally of the ends 61 thereof forming said split 63 sui'- rounding the outer end of the projecting portion 50 of said operating rod 46.

As shown in Fig. 3 thenormal position of the device is with the handle 54 of the operating rod 46 substantially adjacent the hand grip I8 and with the spring 44 normally urging the spike 38 within the lower end of said tubular portion 30.

.When a slippery or icy condition exists the handle 54 is pushed downwardly forcing the radial portion 50 of the operating rod 46 in the vertically extending portion 35 of said slot 36 until it reaches the lower end thereof, simultaneously forcing the inner end 48 thereof and spike 38 attached thereto downwardly so that the pointed end 4D of said spike moves downwardly below the lower end 58 of the tubular member 38 and below lthe .base

8U of the resilient tip T8 as shown in Fig. 2,'f'

with the spring 44 compressing forthis purpose to the position shown. Then the handle 54 mayf be rotated by the thumb tocause the entire operating rod to rotate causing the radially projecting portion 5U thereof to movecircumfe'rentially within the circumferentially extending portionA 31 of the bayonet joint slot 36 with the spring.

The baseV operating against the washer-sl'iapecl projection 88 to urge the spike 38 and operating rod .46` upwardly, pushingthe upper edge of said radial portion 50 of said operating rod 46 against the upper edge of the circumferentially extending portion 31 of said bayonet joint slot to retain the device in operating position with the point 48 of the spike projecting downwardly beyond the lower end of the crutch. To retract the tip 4Q: of the spike within the tubularv member '30it` is obvious that it is merely necessary to rotatey the operating rod until the vradial 4'portion 56' thereof lies in the vertically extendingportion 35 of the bayonet joint slot 36 vwhen the 'spring 44 will push the radial portion 50 vertically upwardly in the slot portion 35 vt0 'move the spike 38 upwardly to Withdraw. the. pointed tip 4U thereof within the lower end' 58 of said'tubular member 30. It is also apparent that the guard 62 attached to said radial portion 5|)v of the operating rod 46 will move therewith to and from the position shown in Fig. 2 to the position shown in Fig. 3, to keep the bayonet joint slot 36 covered at al1 times.

When it is desired to replace the spike 38, it is merely necessary to unscrewV the plug 56, and remove the spike 38 from the lower end of said, operating rod 46 when Said spike 38 may bereplaced by a new one, which may be threaded on to the threaded inner end 4 8 of said operatingrod 46 and the plug 56 reinserted 'withinthe lowerl end 58 of the tubular member 30 and resilient tip 1 8.

It is apparent therefore that we have provided, a novel `type ofv anti-slippingY attachment for the lower kend cfa crutch shank with theadvantages explainedabove. i t

It is understood that our invention is not limited to the specific embodiment 4shown and'that various deviations may be madetherefrom without departing from the spirit and scope 4of .the

other, an arm rest mounted' across the'top of projecting belowthe lower end of the crutch shank having a bayonet joint slot therein, a spike havingv a pointed lowerend and an upper endv movable within the central hollow portion of said tubular member, means contained within the hollow center portion of said tubular memberl for normally urging the pointed lowerend of said spike within said'- tubular member, an operating rod having an inner yend detachably securable to the upper end of said spike for urging the pointed end of said spike downwards to operative position, a locking radial portionfor movement within saidbayonet joint slot, andan operating handle portion beyond said radial portion extending upwardly substantially to the crutch hand grip, av plug having a central spike` hole detachably securable within the lower end of said tubular member whereby said plug and spike may be removed from the lower end ofy said tu-v bular member-for replacement of the spike, and.

a bayonet joint slot guard securable tothe ra dial portion of said operating rodA exterior of said tubular-Ymember.

2. A crutch having the usual spaced. side bars with the lower ends thereof tapering to each other, an arm rest mounted across the top of said side bars, a har-1dV gripimountedbetween said side bars and adjacent the center portions thereof and a shank projecting from the lower ends of the side bars, said crutch being of less length than necessary to support the person, and an anti-slipping attachment of an veffective length to complete the desired length of the crutch, comprising a tubular member having its upper end` surrounding and secured to the lower end of the crutch shank and a central hollow portion projecting below the lower end` of the crutch shank having a bayonet joint yslot therein, aspike having a pointed lower. end and an upper end movable within thecentral hollow portion of saidI tubular member, means contained within the hollow center portion of said tubular member fornormally urging the pointed lower end of said spikewithin said tubular member, an operating rod having an inner end detachably securable to the upper end of said spike for urging the pointed end of said spike downwards to operative position, a locking radial portion for movement within said bayonet joint slot, an operating handle portion beyond said radial portion extending upwardly substantially to the crutch'hand grip and a plug having a central spike hole detachably securable within the lower end of said tubular member whereby said plug and spike may be removed from the lower end of said tubular member for replacement of the spike.

3. A crutch having the usual spaced side bars with the lower ends thereof tapering to each other, an arm rest mounted across the top of said side bars, a hand grip mounted between said side bars adjacent the center portions thereof vand a shank projecting'from the lower ends of the side bars, said crutch being of less length than necessary to support the person, and an anti-slipping' attachment of? anI i eiective length to complete thevdesiredflengthlof the crutch,I corn-i prising` a tubular memberhaving. its upper end:

surrounding and secured tothe lower en'dof the crutch fshaiik'and a centrarhollowf portionl pro`` jecting below ther lowerA end ofl'the crutch shank having a bayonet jointy slot therein, a spike having. a pointed lower end andan 'upper' and mov able within vthe central. lhollow` portion of` saidl tubular member, meansicontained *within the ,hollow center portion of saidv tubular member for normally urging thej'nointedlowe'rv endV of said spike within said tubular 'memben an voperating rod having an inner endrdetach'ablysecurable to the upper end of saidspikeforfurging thepont` led end or said spikedownwards tooperative position, a locking radial' portion Lfor' movement within' said bayonet joint s lot, and an operating handle portion beyond saidfradial" portion eX-' tending upwardly substantially to the crutch hand grip, and a bayonet joint slot guard se` curable to the radial portion'ofsaid operating rod exterior-of said tubular member. f l

4. Anv anti-slipping attachment for` the'lower end of a crutch shank, comprising a tubular member having its upper end adapted tof surround and be secured to the: lower end/iofcthe crutch shank and a central hollow portion adaptedto projectbelowthe lower end of the crutch i shank having a bayonet joint slot therein,v a

spike having a pointed lower-end and an upper` endl movable within the central hollow portion ofv said tubular member, means contained" within the hollow center portion of said tubular member i for normally urging the pointed lowerend of said spike within said tubular member, an operatingl rod having an inner end detachably securable to the upper end of` saidv spike for urging the pointedA end of said spike-downwards to operative position, a locking radial 'portion on said rod:

for movement within said bayonet joint slot, andi an operating handle portion beyond saldi radiali portion, a plug having a central spike hole del tachably securable `within thelower end of said tubular memberwhereby 'said plug and spike may be removed` from the lower end of saidy tubular member for replacement of the'spike, andv a bayonet joint slot guard securable to the radial portion ofi saidy operating rod exterior of `said tubular member.'

5. An anti-slipping attachment'ifor the'lower end of a `crutch shank,' comprising. ai' tubular member having its upper endv adapted to surround and be secured to the lower endl of the-- crutch shank and a central hollow portion adapted to project below the lower end of the crutch shank having a bayonet joint slot therein, a spike having a pointed lower end and an upper end movable within the central hollow portion of said tubular member, means' contained within the hollow center portion of said tubular member for normally urging the pointed lower end of said spike within said tubular member, an operating ro-d having an inner end detachably securable to the upper end of said spike for urging the pointed end of said spike downwards to operative f6. An anti-slipping attachment for the lower end of Va crutch shank, comprising a tubular member having its upper end adapted to surround and be secured tothe lower end of the crutch shank and a central hollow portion adapted to project below the lower end of the crutch shank having a. bayonet joint slot therein, a spike having a pointed lower end and an upper end movable within the central hollow portion of said tubular member, means contained within the hollow center portion of said tubular member for normally urging the pointed lower end of said spike within said tubular member, an operating rod having an inner end detachably securable to the upper end of said spike for urging the pointed end of said spike downwards to operative position, a locking radial portion on said rod for movement within said bayonet joint slot, and an operating handle portion beyond said radial portion, and a bayonet joint slot guard securable to the radial portionv of said operating rod exterior of said tubular member.r

7. An anti-slipping attachment for the lower end of a crutch shank, comprising a tubular member having its upper end adapted to surround and be secured to the lower end of a crutch shank, a central hollow portion projecting below the crutch shank having a bayonet joint slot therein having an axially extending portion and a portion extending circumferentially from the lower end of said axial portion and an internally threaded lower end, a spike having a pointed lower end, and an upper end movable within the hollow center portion of said tubular member having an internally threaded socket in the top thereof and an annular washer shaped portion projecting radially outwardly therefrom, a detachable plug threaded within the lower end of said tubular member having a central bore containing said spike, a resilient tip for said crutch shank having a base having a central spike hole therein and side walls embracing the lower end of said tubular member, spring means interposed between the upper end of said plug and the washer shaped portion of said spike, normally urging said spike upwardly so that the pointed lower end thereof is contained within said tip, means for urging said spike axially of said crutch shank to gripping position, comprising an operating rod having an externally threaded axially extending lower end detachably secured within the threaded socket in the upper end of said spike, a locking portion projecting radially outwardly therefrom to exterior of said tubular member forming with the circumferential portion of said bayonet joint slot, a locking bayonet joint and a portion adapted to project vertically upwardly therefrom terminating in a handle, means for loosely securing said up-v wardly projecting rod portion to said crutch, and a detachable split guard sleeve for said joint slot having aligned partially circular openings therein substantially in the center portions of the ends thereof forming said split, surrounding the outer end of the radially projecting portion of said operating rod.

8. An anti-slipping attachment for the lower end of a crutch shank, comprising a tubular member having its upper end adapted to surround and be secured to the lower end of the crutch shank, a central hollow portion adapted to project below the crutch shank having a bayonet joint slot therein having an axially extending portion and a portion extending circumferentially from the lower end of said axial portion and an internally threaded lower end, a spike having a pointed lower end, and an upper end movable within the hollow center portion of said tubular member having an internally threaded socket in the top thereof and an annular washer shaped portionprojecting radially outwardly therefrom, a detachable plug threaded within the lower end of said tubular member having a central bore containing said spike, a resilient tip for said crutch shank having a base having a central spike hole therein and side walls embracing the lower end of said tubular member, spring means interposed between the upper end of said plug and the washer shaped portion Aof said spike, normally urging said spike upwardly so that the pointed lower end thereof is contained within said tip, and means for urging said spike axially of said crutch shank to gripping position, comprising an operating rod having an externally threaded axially extending 'lower end detachably secured within the threaded socket in the upper end of said spike, a locking portion projecting radially outwardly therefrom to exterior of said tubular member forming with the circumferential portion of said bayonet joint slot, a locking bayonet joint and a portion adapted to project vertically upwardly therefrom terminating in a handle, and means for loosely securing said upwardly projecting rod portion to said crutch.

WILLIAM L. MCGRORY. GEORGE H. PEMBERTON. EDWARD G. MARINETTI. 

